package com.extweb.controller;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import com.extweb.util.PropUtil;

/**
 * 验证码类
 * 
 * @author user
 * 
 */
@Controller
@RequestMapping("/basic/CaptchaController/")
public class CaptchaController {
	private static final Logger logger = LoggerFactory.getLogger(CaptchaController.class);
	private static final int width = 90;/* 定义图片的width */
	private static final int height = 24;/* 定义图片的height */
	private static final int codeCount = 4;/* 定义图片上显示验证码的个数 */
	private static final int xWidth = 18; /* 字符间的距离 */
	private static final int fontHeight = 18;
	private static final int codeY = 18;
	private static final char[] codeSequence = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J', 'K', 'L', 'M', 'N', 'O',
			'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', '0', '2', '3', '4', '5', '6', '7', '8', '9' };

	private static Random random = null; /* 创建一个随机数生成器类 */
	private static StringBuffer randomCode = null;
	/*
	 * randomCode用于保存随机产生的验证码， 以便用户登录后进行验证
	 */
	private static BufferedImage buffImg = null;/* 定义图像buffer */
	private static Graphics gd = null;/* 笔刷 */
	private static Font font = null;/* 笔 */
	static {
		font = new Font("Fixedsys", Font.BOLD, fontHeight);
		random = new Random();
		randomCode = new StringBuffer();
		buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
		gd = buffImg.getGraphics();
		gd.setFont(font); /* 创建字体，字体的大小应该根据图片的高度来定 */
		logger.info("验证码信息初始化");
	}

	@RequestMapping(value = "captcha.sdo", method = RequestMethod.GET)
	public void getCode(HttpServletRequest req, HttpServletResponse resp) throws IOException {
		/* 将图像填充为白色 */
		logger.info("---开始生成图片------");
		
		randomCode.delete(0, randomCode.length());/* 清空数据、重新填入新数据 */
		gd.setColor(Color.WHITE);
		gd.fillRect(0, 0, width, height);
		/* 画边框 */
		// gd.setColor(Color.BLACK);
		// gd.drawRect(0, 0, width - 1, height - 1);

		/* 随机产生40条干扰线，使图象中的认证码不易被其它程序探测到 */
		gd.setColor(Color.BLACK);
		// randomCode.delete(0, randomCode.length());

		for (int i = 0; i < 8; i++) {
			int x = random.nextInt(width);
			int y = random.nextInt(height);
			int xl = random.nextInt(4);
			int yl = random.nextInt(4);
			gd.drawLine(x, y, x + xl, y + yl);
		}

		int red = 0, green = 0, blue = 0;

		/* 随机产生codeCount数字的验证码 */
		for (int i = 0; i < codeCount; i++) {
			/* 得到随机产生的验证码数字 */
			String code = String.valueOf(codeSequence[random.nextInt(34)]);
			/* 产生随机的颜色分量来构造颜色值，这样输出的每位数字的颜色值都将不同 */
			red = random.nextInt(1);
			green = random.nextInt(255);
			blue = random.nextInt(1);

			/* 用随机产生的颜色将验证码绘制到图像中 */
			gd.setColor(new Color(red, green, blue));
			gd.drawString(code, (i + 1) * xWidth - (random.nextInt(12)), codeY);

			/* 将产生的四个随机数组合在一起 */
			randomCode.append(code);
		}
		/* 将四位数字的验证码保存到Session中 */
		HttpSession session = req.getSession();
		// System.out.println(randomCode.toString());
		logger.info("长度为：" + randomCode.length());
		//session.setAttribute(PropUtil.get("kaptcha"), randomCode.toString());
		session.setAttribute("captcha", randomCode.toString());
		/* 禁止图像缓存 */
		resp.setHeader("Pragma", "no-cache");
		resp.setHeader("Cache-Control", "no-cache");
		resp.setDateHeader("Expires", 0);

		resp.setContentType("image/gif");

		/* 将图像输出到Servlet输出流中 */
		ServletOutputStream sos = resp.getOutputStream();
		ImageIO.write(buffImg, "gif", sos);
		sos.close();
	}
}
